Aspirator

ABSTRACT

An aspirator assembly for drawing air into the presence of gas and mixing the gas with the air wherein the gas under pressure is released through a plurality of orifices or nozzles with the flow of the gas from the multitude of orifices serving to provide energy for the inspiration of air into the gas streams and for mixture of the air with the gas in the aspirator assembly.

1 United States Patent 1151 3,659,962 Zink et al. 1 May 2, 1972 [541 ASPIRATOR 2,074,480 3/1937 MacLean ..417/179 x 72 inventors: John Smith Zlnk; Hershel Goodnight; 1580/77 4/1926 suczck x be D R d fT l kl 2,790,595 4/1957 Ebner..... 417/179 X usa'o 838,184 12/1906 Hamel ..417/179 [73] Ass1gnee: John Zink Company, Tulsa, Okla. FOREIGN PATENTS 0R APPLICATIONS [22] 1970 123,059 5/1919 Great Britain ..417/179 121 Appl. No.: 42,775

Primary Examiner-Carlton R. Croyle Assistant Examiner-Richard E. Gluck [52] U.S. Cl ..417/179, 417/198, 239/419.5, Ammey clene Upchurch 239/425.5, 431/350 [51] Int. Cl. ..F04f 5/46, B05b 7/06, F23d 13/40 57 ABSTRACT [58] Field ofSearch ..4l7/l79, 180, 198; 239/4195,

239/4255; 431/350 An aspirator assembly for drawing a1r into the presence of gas and mixing the gas with the air wherein the gas under pressure [56] Reierences Cited is released through a plurality of orifices or nozzles with the flow of the gas from the multitude of orifices serving to pro- UNITED STATES PATENTS vide energy for the inspiration of air into the gas streams and for mixture of the air with the gas in the aspirator assembly. 3,572,974 3/1971 Day ..417/l79 2,068,748 1/1937 Kleir ..417/180 3 Claims, 8 Drawing Figures Patented May 2, 1972 2 Sheets-Sheet l INVEN TORS JOHN 544/ TH Z/NK HE RSHE L GOODN/GH T ROBERT D. REED S A 414* ATTORNEY Patented May 2, 1972 3,659,962

2 Sheets-Sheet 2 ASPIRATOR The present invention relates to an aspirator assembly wherein the discharge of gas serves to develop low pressure conditions adjacent the flowing gas which serves to draw at mospheric air into the presence of the escaping gas and provide an air-gas mixture and the invention more specifically pertains to the release of the gas through a plurality of orifices so as to more fully utilize the energy conversion of the escaping gas streams.

Atmospheric aspirators are well known and are in general use. The gas under pressure has in the past been released through a single orifice into the throat of the aspirating assembly. The energy developed from the flowing gas is the result of the pressure at which the gas is stored and which is greater than atmospheric pressure. The energy which creates the inspiration of air for mixture with the gas is derived from velocity at which the gas is released into the throat of the aspirator assembly. This velocity is the greatest at the exit end of the orifice and it is at this zone that there is a maximum potential for energy conversion in the inspiration of air.

An object of the present invention is to provide structure for the access of air to the area immediately adjacent the exit ends of a plurality of orifices through which the gas is discharged into the throat of an aspirator assembly so that there is less loss of energy than would be the case of a single orifice having a flow capability substantially equal to the plurality of orifices.

Another object of the invention is to provide an atmospheric aspirator assembly wherein the gas is released into the throat of the assembly through a plurality of orifices to provide improved air inspiration into the throat and which is increased by as much as 4% percent and with a decrease in the noise produced from I decibel in the 150 to 300 cycle range and with the noise reduced by as much as ll decibels in the frequency range of 1,200 to 4,800 cycles per second.

Other objects and features of the invention will be appreciated and become apparent as the present disclosure proceeds and upon consideration of the following detailed description taken in conjunction with the accompanying drawings wherein several embodiments of the invention are disclosed.

FIG. 1 is a longitudinal sectional view of an aspirator assembly embodying the invention.

FIG. 2 is a sectional view taken on the line 22 ofFIG. 1.

FIG. 3 is a sectional view taken on the line 3--3 of FIG. 1.

FIG. 4 is a fragmentary longitudinal section of a modification.

FIG. 5 is a sectional view taken on the line 55 of FIG. 4.

FIG. 6 is a longitudinal section of another form of structure for releasing gas through a plurality of orifices.

FIG. 7 is a sectional view taken on the line 7-7 of FIG. 6.

FIG. 8 is a sectional view taken on the line 8-8 of FIG. 6.

The invention is directed to an assembly for aspirating air into gas as it is discharged into the tubular portion where the gas and air are mixed and to an aspirator assembly wherein atmospheric air is available at the exit end of each of a plurality of orifices through which gas is discharged into the throat of an aspirator assembly.

There is shown in FIG. 1 a tubular member 10 which provides an elongated chamber 11 in which the gas is mixed with air to provide an air-gas mixture. The upstream end portion of the tubular member 10 is of flared construction to provide a trumpet-shaped mouth 12. The interior surface 14 of the tubular member 10 is of cylindrical shape for a distance of four times the diameter measured downstream from the exit end of a discharge orifice for the gas. Thereafter the interior surface 15 flares outwardly to provide a frusto-conical surface to allow for expansion of the gas-air mixture. Such portions of the aspirator assembly are of known construction and provides for the discharge of gas from a single orifice which is aligned with the axis of the tubular member 10. The movement of the gas provides energy for inspirating air into the mouth of the tubular member 10.

The present invention is directed to an aspirator assembly wherein the gas is released from a plurality of orifices for movement into the throat of the tubular member 10. A pipe 16 extends from a source of gas under pressure and the gas moves into a conduit member 17 as shown in FIG. 1. A plate element 18 may be welded or otherwise secured to the conduit member 17 and is attached to the tubular member 10 by a plurality of cap screws 19. The cap screws extend into threaded engagement with the flared mouth portion 12 of the tubular member 10 and the plate element 18 is maintained in spaced relationship from the upstream end of the tubular member 10 by spacer elements 21 which surround the cap screws 19.

A plurality of orifices are provided in the plate element 18 for the escape of gas from the chamber 22 formed in the conduit member 17. In the embodiment shown in FIG. 1, orifices 23 are provided by noules 24 which are carried by the plate element 18 and are in communication with the chamber 22. The nozzles 24 are circumferentially spaced from each other as shown in FIG. 2.

The velocity of the escaping gas is at a maximum adjacent the exit ends of the nozzles 24 and it is in this zone that there is a maximum potential for energy conversion for the inspiration of air. Air at atmospheric pressure is accessible to the exit ends of the nozzles 24 and at the exit ends of the orifices 23 through the open area between the plate element 18 and the flared mouth portion 12 of the tubular member 10. Atmospheric air is available adjacent the exit ends of the orifices 23 and there is less loss of energy than would be the case with a single orifice having a flow capability equal to the plurality of orifices 23 shown in FIGS. 1 and 2. The air is available at the exit ends of the orifices 23 and there is a greater quantity of energy produced by the flowing gas for the work involved in the inspiration of air. The energy of the flowing gas is thus more efl'rciently utilized by as much as 4% percent over an aspirator assembly wherein the gas is released through a single orifice. The dispersion of the orifices 23 within an area defined by the interior surface 14 of the tubular member 10 provides a reduction in the noise produced by the escaping gas and the inspiration of the air into the tubular member.

In another embodiment of the invention, the gas from the supply pipe 16 is discharged into a conduit fitting 26 which has a plate-shaped portion 27 supported in spaced relationship from the upstream end of the tubular member 10. The gas moves through the plate-shaped member 27 into a pipe portion 28. One discharge orifice 33 is aligned with the axis of the tubular member 10. A plurality of conduits 34 in communication with the interior of the pipe portion 28 terminate in discharge orifices 36 which are circumferentially spaced from each other around the axis of the assembly. Air at atmospheric pressure is available at the exit ends of the discharge orifices 36 and the discharge orifice 33 where movement of the escaping gas is at a maximum velocity. The air moves into the presence of the streams of escaping gas through the open areas between the spacer elements 21. The energy of the flowing gas stream is utilized with maximum efficiency in the inspiration of air.

Another embodiment is shown in FIGS. 6 to 8 wherein the gas under pressure is supplied into a conduit fitting 37 equipped with a plate portion 41 supported in spaced relationship from the upstream end of the tubular member 10. A pipeelement 42 receives the gas from the supply pipe 16. The gas is delivered into a plurality of hollow radially disposed arms 46. A plurality of orifices 47 are provided in each arm as shown in FIGS. 6 and 7. Air at atmospheric pressure is available at the exit ends of the discharge orifice 47 where the velocity of the escaping gas is at a maximum so that there is efficient utilization of the flow energy for inspirating air into the tubular member 10.

While the invention has been described with reference to specific structural features regarding elements making up circumferentially spaced discharge orifices, it will be appreciated that changes may be made in the structural elements as well as the overall organization. Such modifications and others may be made without departing from the invention as set forth in the appended claims.

What is claimed and desired to be secured by Letters Patent 1s:

1. An aspirator comprising a tubular member having an open upstream end adjacent a substantially cylindrical throat and an integral outwardly flaring downstream portion, a plate member spaced longitudinally from the said open upstream end and secured thereto by circumferentially space cap screws and spacer elements to provide an otherwise open space between the said open end and the plate member, a centrally disposed orifice in the plate member, a nozzle disposed in said unenclosed space secured at one end to the plate member with its passageway communicating with the centrally disposed orifice, said nonle comprising a plurality of circumferentially spaced radially extending hollow arms which communicate with said passageway and have a plurality of orifices therein, the dispersion of the orifices in the hollow arms being within an area defined by the interior of the said throat, and means for passing gas under pressure through the orifice in the plate member.

2. The aspirator of claim 1 wherein the length of said throat is about four times its internal diameter.

3. An aspirator assembly comprising a tubular member having a substantially cylindrical throat adjacent an open upstream end, means comprising a plate member spaced longitudinally from said open end and having a centrally disposed orifice, a conduit secured at one end to the plate member about the said orifice and terminating in the space between the plate member and the said open end in a plurality of circumferentially spaced radially extending hollow arms, a plurality of orifices in said arms which are adapted to direct gas into said open end, said tubular member and conduit having a common axis, and means for passing gas under pressure through the conduit, the space between said open end and said plate member being substantially unenclosed about said arms whereby air under atmospheric pressure is available for inspiration as the gas streams move from the orifices in the hollow arms towards the said open end. 

1. An aspirator comprising a tubular member having an open upstream end adjacent a substantially cylindrical throat and an integral outwardly flaring downstream portion, a plate member spaced longitudinally from the said open upstream end and secured thereto by circumferentially space cap screws and spacer elements to provide an otherwise open space between the said open end and the plate member, a centrally disposed orifice in the plate member, a nozzle disposed in said unenclosed space secured at one end to the plate member with its passageway communicating with the centrally disposed orifice, said nozzle comprising a plurality of circumferentially spaced radially extending hollow arms which communicate with said passageway and have a plurality of orifices therein, the dispersion of the orifices in the hollow arms being within an area defined by the interior of the said throat, and means for passing gas under pressure through the orifice in the plate member.
 2. The aspirator of claim 1 wherein the length of said throat is about four times its internal diameter.
 3. An aspirator assembly comprising a tubular member having a substantially cylindrical throat adjacent an open upstream end, means comprising a plate member spaced longitudinally from said open end and having a centrally disposed orifice, a conduit secured at one end to the plate member about the said orifice and terminating in the space between the plate member and the said open end in a plurality of circumferentially spaced radially extending hollow arms, a plurality of orifices in said arms which are adapted to direct gas into said open end, said tubular member and conduit having a common axis, and means for passing gas under pressure through the conduit, the space between said open end and said plate member being substantially unenclosed about said arms whereby air under atmospheric pressure is available for inspiration as the gas streams move from the orifices in the hollow arms towards the said open end. 